Linear LED modules are an example of lighting devices exhibiting modularity. Modularity in a product enables cutting the module to length at certain fixed points.
In various implementations, the cutting points and the corresponding circuit are visible to the final user from the front or top side (i.e. the side carrying the light radiation sources, e.g. the LEDs) or they may be made visible via a particular marking (e.g. ink or laser printing).
In a protected module, where no transparent materials are used, the cutting points which may be present on the device support (for example a Printed Circuit Board, PCB) may not be recognizable through a direct observation of the circuit and/or the marking. When an opaque material is used, it is impossible to identify the cutting points by observing the position of the LEDs or the associated electronics, which are not visible. This is an intrinsic limit for those applications wherein the module must be cut to length.
This problem may be countered in protected modules through a marking (e.g. a laser marking) of cutting points on one side of the module. The alignment of cutting points may be based on the position of the light radiation sources, adapted to be the only visible components.
This approach is critical due to the tolerances of the marking, to the possible shrinkage of different materials during the process and to the need, in the positioning of the module, of aligning the marking with the layout of the support (e.g. of the PCB).
These problems have been found to be virtually unsolvable if the support (e.g. the PCB) and/or the components are not visible to the final user, so that the module may be cut but, for example, without offering the possibility to reconnect a part of the module.